title: Definition, categorization, and terminology of episodic breathlessness: consensus by an international Delphi survey.
abstract: BACKGROUND
  Episodic breathlessness is a common and distressing symptom in patients with advanced disease. Still, it is not yet clearly defined.
  
  
  OBJECTIVE
  The aim of this work was to develop an international definition, categorization, and terminology of episodic breathlessness.
  
  
  METHODS
  An online Delphi survey was conducted with international breathlessness experts. We used a structured questionnaire to identify specific aspects and reach agreement on a definition, categorization, and terminology (five-point Likert scale). Consensus was defined in advance as ≥70% agreement.
  
  
  RESULTS
  Thirty-one of 68 (45.6%), 29 of 67 (43.3%), and 33 of 67 (49.3%) experts responded in the first, second, and third rounds, respectively. Participants were 20-79 years old, about 60% male, and more than 75% rated their own breathlessness expertise as moderate to high. After three rounds, consensus was reached on a definition, categorization, and terminology (84.4%, 96.3%, and 92.9% agreement). The final definition includes general and qualitative aspects of the symptom, for example, time-limited severe worsening of intensity or unpleasantness of breathlessness in the patient's perception. Categories are predictable or unpredictable, depending on whether any triggers can be identified.
  
  
  CONCLUSIONS
  There is high agreement on clinical and operational aspects of episodic breathlessness in advanced disease among international experts. The consented definition and categorization may serve as a catalyst for clinical and basic research to improve symptom control and patients' quality of life.
authors.affiliation: Department of Palliative Medicine, University Hospital of Cologne, Cologne, Germany; Centre for Integrated Oncology Cologne/Bonn, Clinical Trials Centre Cologne (BMBF 01KN1106), Cologne, Germany. Electronic address: steffen@steffensimon.de.
authors.forename: Steffen T
authors.initials: ST
authors.lastname: Simon
authors.affiliation: Department of Palliative Medicine, University Hospital of Cologne, Cologne, Germany.
authors.forename: Vera
authors.initials: V
authors.lastname: Weingärtner
authors.affiliation: King's College London, Cicely Saunders Institute, Department of Palliative Care, Policy and Rehabilitation-WHO Collaborating Centre for Palliative Care and Older People, London, United Kingdom.
authors.forename: Irene J
authors.initials: IJ
authors.lastname: Higginson
authors.affiliation: Department of Palliative Medicine, University Hospital of Cologne, Cologne, Germany; Centre for Integrated Oncology Cologne/Bonn, Clinical Trials Centre Cologne (BMBF 01KN1106), Cologne, Germany.
authors.forename: Raymond
authors.initials: R
authors.lastname: Voltz
authors.affiliation: King's College London, Cicely Saunders Institute, Department of Palliative Care, Policy and Rehabilitation-WHO Collaborating Centre for Palliative Care and Older People, London, United Kingdom; Department for Palliative Medicine, University Hospital of Munich, Munich, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Bausewein
mesh_terms: D000328:Adult; D000368:Aged; D032921:Consensus; D003697:Delphi Technique; D018450:Disease Progression; D004417:Dyspnea / Q000145:classification* / Q000175:diagnosis / Q000209:etiology; D005260:Female; D006801:Humans; D038622:Internationality; D020407:Internet; D008297:Male; D008875:Middle Aged; D010507:Periodicity; D009626:Terminology as Topic; D055815:Young Adult
keywords: Delphi method; dyspnea; episodic breathlessness; palliative medicine; respiratory symptoms